// 例子24

var str = '1 plus 2 equals 3';
str.match(/\d+/g) // ["1", "2", "3"]

var url = /(\w+):\/\/([\w.]+)\/(\S*)/;
var url2 = /(\w+):\/\/([\w.]+)\/(\S*)/g;
var text = 'Visit my blog at http://www.example.com/~david';
var result1 = text.match(url); // ["http://www.example.com/~david", "http", "www.example.com", "~david"]
var result2 = text.match(url2); // ["http://www.example.com/~david"]